Shaws in Ireland
Some sources assert that all Shaws in Ireland are descended from a Captain William Shaw, who served in Cromwell's army in 1649, in Colonel Ponsonby's regiment. Ponsonby was knighted, and both were granted lands confiscated from Catholics, as a reward for their loyalty.
This Captain William Shaw certainly existed, although other Shaws are mentioned as serving in Cromwell's army. It is possible that William Shaw came from the Cheshire area and that he was related to Ponsonby by marriage.
Other sources claim that Irish Shaws descend from a Captain or Colonel Shaw who served in General Ponsonby's Horse in the Army of William III. One version of this story is that Shaw carried the wounded Ponsonby off the field at the Battle of the Boyne in 1690. Both Shaw and Ponsonby received land in Kilkenny and Tipperary for their efforts. But documents from the period list (for example) a Patrick Shaw, three William Shaws, and James Shaw as among the founders of the Antrim Association, founded to raise and organize protestant defences during the siege of Derry in 1689.
I believe that several Shaws, possibly distantly related, came to Ireland with Cromwell and settled there, and poosibly that others came with William of Orange. However, all were protestants. Wexford history refers to Shaws as protestants planning to emigrate in the early 1800's and others as being imprisoned and killed in the Catholic uprising of the same period.